Same here, I had no idea this game was made. Wonder how we missed it?
Perhaps it was planned to be on an official website but got cancelled for some reason.

I do remember that there was a Nickelodeon website for the movie with several games and clips on it, but don't remember this game being on there.
The website was http://tmntmovie2.com by the way.
It re-directs me to the Nickelodeon homepage.